“Recipe” type practical work can leave students with the impression that research “proves” a foregone conclusion, and that when investigations do not go as predicted a mistake of some sort has been made. Journalists sometimes pick up on such instances when research is controversial, in order to sensationalise the inadequacies of the science (as they choose to portray these). As informed adult citizens, students will need to be aware that disconfirming evidence can be just as important, if not more so, than evidence that confirms a prediction. Disconfirming evidence does signal that the explanation is not yet correct, but then the purpose of investigations is to test ideas, not just to rubber stamp them.
Developing an appreciation of what counts as evidence in science supports students to become scientifically literate, i.e., to participate as critical, informed, and responsible citizens in a society in which science plays a significant role. (This is the purpose of science in NZC.)